It is recommended to disable Ultimate Cron's poorman's cron function, and instead setup the crontab on the server to run each minute, e.g.:

* * * * * wget -O - -q -t 1 http://www.example.com/cron.php

Ultimate Cron will launch each Drupal cron handler at it's configured time. By default, all queues run each minute, and all regular jobs run every 10 minutes, with a slight offset to each other. The default rule can be configured on the Ultimate Cron settings page.

If wget isn't triggering your crontab, check to see if the curl command is installed on your server and use it instead.

* * * * * curl http://www.example.com/cron.php

If you are on Drupal 7, you might have to get the full "outside" cron.php?cron_key=[token value] from your /admin/reports/status page and use it instead of just "cron.php". You can find it under the Cron maintenance tasks section. This is also the same area where you can see if your crontab is working properly. If it is, the "Last run" should never be more than 60 seconds.